| Title |
Adaptive Numerology-DMRS Technique to Maintain Data Throughput-based QoS in 5G NR V2X |
| DOI |
https://doi.org/10.5573/ieie.2022.59.8.3 |
| Keywords |
Cellular V2X; 5G NR; Throughput; Numerology; DMRS |
| Abstract |
Maintaining stable data throughput in V2X services such as remote driving is one of the most important requirements. When the moving speed of UE (User Equipment) is high, since the channel characteristics change rapidly, reliable communication in a time varying frequency selective fading environment must be achieved. In LTE or 5G NR standards, a demodulation reference signal (DMRS) is transmitted and used for channel estimation at the receiving end. In 5G NR, numerology can be variably set, so sub-carrier spacing (SCS) is variable, and the number of DMRS symbols per slot can also be variably applied. In this paper, we propose a technique to maintain the target data throughput even under fluctuating channel environment conditions by adaptively setting numerology parameters and DMRS symbols per slot by recognizing the channel environment in 5G NR based V2X systems. The feature of this algorithm is that, in addition to using the DMRS symbol for demodulation, it is used to estimate the delay spread of the channel. Link-level simulation was performed to evaluate the performance of the proposed adaptive numerology-DMRS system. We analyzed whether the target data throughput can be maintained in a complex environment where the delay spread of the channel changes while the UE moves at various speeds, and the performance of the proposed system was compared and evaluated with the system using fixed parameters. |